Leland Stanford Junior University

Craig S Criddle

Brian J Cantwell

Yaniv D Scherson

Xing Xie

Yi Cui

George F Wells

Meng Ye

Allison J Pieja

Eric R Sundstrom

Curtis W Frank

Mauro Pasta

Sarah Billington

Sindy Tang

Koshlan Mayer-Blackwell

Kevin Lohner

Vaishnav V Davey

Margaret C Morse

Sarah J Christian

Jaewook Myung

Minkyu Kim

Katherine H Rostkowski

Described here is a method for increasing the transfer of a gas substrate in microbial fermentation, comprising incubating an emulsion comprising an oil phase and an aqueous phase droplet dispersed in the oil phase, and supplying the gas substrate to the oil phase, wherein the aqueous phase droplet comprises a microorganism, and wherein the emulsion is stabilized by a surfactant or an amphiphilic particle that is adsorbed to an interface of the oil phase and the aqueous phase. Also described is an emulsion for microbial fermentation, comprises an oil phase and an aqueous phase droplet dispersed in the oil phase, wherein the aqueous phase droplet comprises a microorganism, wherein the emulsion comprises a gas substrate externally-supplied to the oil phase, and wherein the emulsion is stabilized by a surfactant or an amphiphilic particle that is adsorbed to an interface of the oil phase and the aqueous phase.

Emulsion-based fermentation for accelerated gas substrate mass transfer

Described herein is a mixing entropy battery including a cationic electrode for sodium ion exchange and an anionic electrode for chloride ion exchange, where the cationic electrode includes at least one Prussian Blue material, and where the mixing entropy battery is configured to convert salinity gradient into electricity.

Charge-free mixing entropy battery

A microbial battery is provided. At the anode, microbial activity provides electrons to an external circuit. The cathode is a solid state composition capable of receiving the electrons from the external circuit and changing from an oxidized cathode composition to a reduced cathode composition. Thus, no external source of oxygen is needed at the cathode, unlike conventional microbial fuel cells. The cathode can be removed from the microbial battery, re-oxidized in a separate oxidation process, and then replaced in the microbial battery. This regeneration of the cathode amounts to recharging the microbial battery.

Microbial batteries with re-oxidizable solid-state electrodes for conversion of chemical potential energy into electrical energy

A method of high throughput growth and quantitative analysis of microorganisms is provided that includes providing a microtiter plate growth and gas delivery system having well plates disposed for growth of the microorganisms, and providing a spectroscopic screening system disposed to analyze lipid inclusions of the microorganisms.

High throughput system for isolation, growth, and detection of lipid inclusions in bacteria

A method of selection for type II methanotrophs is provided that includes enriching a microbial feedstock using a non-sterile bioreactor with a methane source and a nitrogen source, where the microbial feedstock includes a mixture of Type I and Type II methanotrophic cells, where an inhibited growth of the Type I methanotrophic cells and an enhanced growth of the Type II methanotrophic cells forms. The method further includes exposing intermittently the enriched microbial feedstock to i) nitrate, ii) urea, or i) and ii), where enhanced growth of the Type II methanotrophs is established, and exposing the Type II methanotrophs to an unbalanced growth condition where production of polyhydroxybutyrate is induced.

Process for the selection of PHB-producing methanotrophic cultures

A bioreactor designed to produce NO from organic nitrogen and/or reactive nitrogen in waste is coupled to a hardware reactor device in which the NO is consumed in a gas phase chemical reaction, e.g., catalytic decomposition to form oxygen and nitrogen gas. Heat from the exothermic reaction may be used to generate power. The bioreactor may use communities of autotrophic microorganisms such as those capable of nitrifier denitrification, ammonia oxidizing bacteria, and/or ammonia oxidizing archaea. A portion of the NO dissolved in aqueous effluent from the bioreactor may be separated to increase the amount of gas phase NO product. The amount of the gas phase NO in a gas stream may also be concentrated prior to undergoing the chemical reaction. The NO may alternatively be used as an oxidant or co-oxidant in a combustion reaction, e.g., in the combustion of methane.

Microbial production of nitrous oxide coupled with chemical reaction of gaseous nitrous oxide

A bioreactor designed to produce NO from organic nitrogen and/or reactive nitrogen in waste is coupled to a hardware reactor device in which the NO is consumed in a gas phase chemical reaction, e.g., catalytic decomposition to form oxygen and nitrogen gas. Heat from the exothermic reaction may be used to generate power. The NO may alternatively be used as an oxidant or co-oxidant in a combustion reaction, e.g., in the combustion of methane. The bioreactor may have various designs including a two-stage bioreactor, a hollow-fiber membrane bioreactor, or a sequencing batch reactor. The bioreactor may involve Fe(II)-mediated reduction of nitrite to nitrous oxide.

A method to produce NO from organic nitrogen and/or reactive nitrogen in waste uses a bioreactor coupled to a hardware reactor device in which the NO is consumed in a gas phase chemical reaction, e.g., catalytic decomposition to form oxygen and nitrogen gas. Heat from the exothermic reaction may be used to generate power. The NO may alternatively be used as an oxidant or co-oxidant in a combustion reaction, e.g., in the combustion of methane.

Microbial production of nitrous oxide coupled with chemical reaction of gaseous nitrous oxide including phosphorus recovery and nitrite reduction to nitrous oxide

A method for inexpensive and efficient PHA biosynthesis includes operating a sequencing bioreactor in alternating phases of nutrient deprivation and carbon feedstock deprivation to select for robust PHA-producing microbes. Preferably, the bioreactor is operated in a non-sterile manner with mixed cultures of methanotrophs. The method also preferably uses periodic biomass-wasting (PHA harvesting) at the end of the carbon feed phase, gradually lengthening the time period of carbon deprivation phase to create a penalty for rapid PHA degradation and incentive for PHA accumulation. Also, bacterial enrichment cultures may be introduced periodically. The PHA-accumulating bacteria are preferably grown on common anaerobic degradation products, specifically volatile fatty acids, such as acetate and propionate, and methane gas. The PHA has useful applications in bioplastics and other products.

Use of selection pressures to enable microbial biosynthesis of polyhydroxyalkanoates from anaerobic degradation products

A biocomposite is produced from natural fiber fabrics embedded in a matrix of biosynthetic polyhydroxy-alkanoate (PHA) polymers. The PHA is synthesized using aerobic microbial biosynthesis using mixed bacterial cultures and a feedstock containing anaerobic degradation products such as methane and volatile fatty acids derived from microbial biodegradation of organic waste materials, which may include waste biocomposites. Monomers may be added to the synthesized PHA polymer to control mechanical properties of the resulting biocomposite. The natural fibers and/or PHA may be pretreated using various techniques to improve the bond between the fibers and the PHA resin matrix and water absorption resistance of the fibers. The composite may be a laminate of treated and untreated fabric layers, or differently treated layers, to achieve good in-service performance as well as rapid and/or optimal biogas production when taken out of service and put in an anaerobic environment to degrade.

Growing community of inventors

Redwood City, CA, United States of America

Craig S Criddle